William c



(No Model.) I V W. O. MAOKINNEY.

- 'VAGUUM VALVE. v No; 284,452. I Patented Sept. 4, 1883 .FZG. 3.

N. PEIERs. Hwwumo m mr. Walhingicn. 12.0

- UNITED STATES.

PATENT OFFICE.

, WILLIAM C. MAOKINNEY, on PHILADELPHIA, PENNSYLVANIA, ASSIGNOB TO JAMESBUTTERWORTH, CHARLES C. BUTTERWORTH, AND WILLIAM B. BUTTERWORTH, ALL OFSAME PLACE. r

vAcuuMj-vALvE.

SPECIFICATION forming part of Letters Patent No. 284,452, dated.September 4, 1883.

' Application filed April 2, 1883. (No model.)

ments, fully described hereinafter, in vacuumvalves fordrying-cylinders; and the object of .10 my improvements is to soconstruct the easing of the valve and to so combine it with the latterthat the direct and instantaneous admission of air into thedrying-cylinder will be assured whenever a partial vacuum occurs Itherein, all danger of the collapsing of the cylinder being thusobviated. I In the accompanying drawings, Figure l is a sectional viewof my improved vacuumvalve; Fig. 2, a view of one end of the valve- 2ocasing; Fig. 3, a section on the line 1 2, Fig.

1; and Fig. 4., views of the several parts detached from each other. l

My invention is intended, mainly, for hollow steam-heated cylinders fordrying fabrics,.pa-

per, &c., A in Fig. 1 representing part of one of the ends or heads ofsuch cylinder.

The casing of the valve consists of the eX- ternally-threaded andflanged ring B and the smaller ring, a, which is connected to the main 0ring by legs bfour in the present instance as shown in Fig. 3, so thatthere are openings w between the legs. A seat, cl, is formed on theinner end of the main ring B of the casing, for

thevalve D, which has'two stems, e and e,

the former being adapted to a guide, f, connected to the ring B by websh, and the spindle 6 being adapted to a guide, 9, connected by webs toand forming a part of an externally-threaded ring, E, which is screwedinto 40 the ring a of the casing, the latter ring being of such adiameter internallyas to permit the withdrawal of the valve from and itsintro duction into the casing when been detached therefrom.

WVhen a machine of which a drying-cylinder forms a part is in operation,steam at a o mparativelylow pressure is maintained within the cylinder;but occasionally the latter bethe ring E has I comes cooled--by wetfabrics, for instance and this causes a condensation of steam, andconsequently a partial vacuum, and if this is not at once neutralized bythe admission of air the collapsing of the cylinder will take place.Avacuumvalve for this purpose should be instantaneous in its action andsimultaneous with the formation of the partial vacuum;

not be avoided. A vacuum-valve with tortuous passages might retard theadmission of air for an instant, but long enough to permit thecollapsing of the cylindera result which my improved valve has beendesigned to obviate.

screwed into or otherwise secured to the head A of the drying-cylinder,the valve remaining closed by the pressure of steam in the saidcylinder; but should a partial vacuum be crecauses, therewill be aninstant opening of the valve by the pressure of the atmosphere on intothe cylinder to neutralize the partial vacuumbefore any collapsing ofthe cylinder can take place. In the first place it will be noted thatthe valve isso guided that it will be opat a comparatively low pressureto maintain it in contact with its seat, or of the external partialvacuum occurs within the cylinder, and the moment the valve leaves itsseat under these circumstances there will be an instantaneous and directintroduction of a large and diffused volume of air into the cylinder toneutralize the partial vacuum, for it will be seen that the ring B ofthe valve-casing terminates at the inner face of the cylinder-head, andthat the seat of the valve is at the inner end .of this ring and closeto the openings w between the legs 12 of the casing; hence the move mentof the valve induced by a partial vacuum in the cylinder will permit theair to pass directly into the same through the said open ings w in thedirection pointed out by the inclined arrows, aswell as through theopenings otherwise the collapsing of the cylinder may 'The threaded ring13 of the valve-casing isv ated therein, owing to the above-mentioned,

air to move the valve from the seat when a its exterior surface, and aninstant rush of air erated by the slightest effort either of steam airfrom the cylinder before the valve is actu ally closed.

I claim as my invention' 1. The combination of the valve D and its I twostems e 6 with a casing open at its outer end, and affording a seat forthe valve and guides for its two stems, and having openings w close tothe said seat, all substantially as set forth.

2. The combination of the casing, consist ing of the cylinder B, open atits outer end, its guide f, legs 1), ring a, and detachable ring E,having a guide, g, with the valve and its two stems, substantially asspecified.

In testimony whereof I have signed my name to this specification in thepresence of two sub- 20 scribing witnesses.

WILLIAM C; MAGKINNEY.

